Work is currently in progress on the following problems: 1. Displacements of the cochlear partion, measured by a laser interferometer; 2. assessment of bone conduction input to the human head; 3. determination of the shape of the tympanic membrane by a moire technique. BIBLIOGRAPHIC REFERENCES: Tonndorf, J. "Davis -- 1961, Revisited." Arch. Otolaryng. Vol. 101, pp. 528-535, 1975. Tonndorf, J. Auditory Physiology, The Processing of Acoustic Information, an Introduction for Physicians, Biologists, Psychologist, and Communication Engineers. Edited by W. K. Keidel, Ann. Oto-Rhino-Laryng. 84, p. 721, 1975.